The present invention relates generally to printing presses and, more specifically, to a system for cooling ink and/or coatings on printing presses.
It is known that the normal operation of a printing press produces heat. On many printing components, this heat may be the result of friction. For example, the anilox roll makes direct contact with the doctor blades in the chamber doctor blade system. Friction between the doctor blades and the anilox roll may cause one or more of these components to heat up. Further, friction between the anilox roll and other components, such as the plate cylinder, likewise may cause the anilox roll and other components to generate still additional heat. Still further heat is generated by plate rolls and other press components, such as, for example, dryers. Finally, additional heat may result from the ambient heat in the press room.
According to normal thermodynamic processes, the generated heat is readily transferred to the ink used on the printing press. In some press components, such as the aforementioned chamber doctor blade system, a relatively small quantity of ink may be exposed to a relatively high and localized heat source. Furthermore, the chamber or the pan may function as a heat sink, providing another avenue for routing heat to the ink.
As the ink heats up, various components of the ink may be lost, such as, by way of example rather than limitation, volatiles, solvents, amines, etc. Unfortunately, this heated and altered ink tends to have a detrimental effect on the overall quality of the printing operation. Additives and the labor or equipment required to correct the ink properties add additional expense. Accordingly, it may be desirable to cool the ink in order to prevent the negative impact on print quality. However, merely cooling the general ink supply is not sufficient to address the localized heating that occurs at some of the press components. The foregoing discussion may be equally applicable to coating systems which apply liquid coatings to a web or other substrate in a printing press.